Life moves at a quick pace these days, so the time we've spent sleeping is time wasted where we've missed out on precious new information.

Who knows what the Kardashians have been up to in the eight hours we were resting our minds to tackle the next day's tasks? What Facebook status has your friend posted that you can get annoyed about next? We'll never know, at least not until we wake up tomorrow. However, if you find that you're struggling to stay awake as the hours tick by into the early morning, your smartphone could be to blame.

There are plenty of studies that back this up for a number of different reasons, but the latest in the series is from Norway, where a survey that took two years to produce looked at 9,846 teenagers aged 16 to 19, and was published this week in the journal BMJ Open.

The study found that almost all of them reported using one form of electronic device in the hour leading up to going to sleep, and that "extensive use of these devices was significantly and positively associated with SOL [sleep onset latency; essentially how long it takes you to go to sleep] and sleep deficiency, with an inverse dose–response relationship between sleep duration and media use". That's science speak for the fact that using the device makes it more difficult to get to sleep.

According to Mashable, there are several reasons for this, but that blueish light emitted by LED screens stops your brain from producing the sleep hormone melatonin, while playing a game can elicit the flight-or-fight response, even if it's something as tame as Candy Crush. The study says that there are many reasons for the reaction that causes you to have difficulty sleeping, stating that "media use may directly affect sleep by replacing it due to its time-consuming nature, or may interfere with sleep through increased psychophysiological arousal".

The simple act of holding your phone or scrolling through your social media can also bring about that type of reaction in your brain, given that we associate the device with exciting activities like getting new information and socialising or getting messages from friends.

While researchers were keen to point out that more work is needed on this topic, the signs are pretty clear that flicking around on your smartphone before you head to bed is not helping if you're having difficulty sleeping. Their best suggestion is to read a slow-paced book, ideally on actual paper, that lets your brain now that it's time to start shutting down, while if you have a dedicated reading device, it's better to use that than a phone or tablet.

Via Mashable. Main pic via Highways Agency/Flickr